System and method for production of a renewable liquid fuel

ABSTRACT

A system and method for torrefying a combination of biomass and biochar colloidal dispersion is provided.

BACKGROUND

The present invention relates generally to fuels derived from processedbiomass, and more particularly to fuels that are a colloidal dispersionof heat-treated charred biomass generally processed in the absence ofoxygen that can be used as substitutes for, or additives to, fluidbio-oil based fuels, and fluid petrochemical fuels.

It is widely recognized that the majority of energy produced throughoutthe industrialized world is based on the consumption of petroleum basedliquid fuels. Such fuels have a high energy density, are relatively easyto transport and store, and can be used in a wide variety of engines andheaters. However, as is common knowledge, the in-ground stores ofpetroleum based products are rapidly declining, and experts predict thatnew discoveries are not occurring frequently enough to offset the rapiddrawdown of currently known reserves. In the parlance of today, theseresources are considered to be non-renewable. Furthermore, use of thesenon-renewable resources are believed to produce climate changes and moreimmediately identified local environmental effects commonly associatedwith increased fouling of air and water and are generally consideredpollution inducing and having a negative effect on the environment.

Various attempts have been made to identify renewable sources of energythat can be used in place of petroleum based fuels. For example,electricity can be generated using such renewable energy sources aswind, solar, geothermal and hydroelectric. While these energy sourcesare considered “clean” or “green” because they are renewable, relativelynon-polluting, and are thought to produce a minimal to no carbonfootprint or reduced emission profile on the environment from their use,they each have drawbacks due to location, convertibility, space, andwind and water availability. Essentially, these renewable resources arenot always found in sufficient commercially available amounts in thelocations where they are needed to enable their substitution for allcommercially used non-renewable resources.

Coal is another source of energy that is widely used, but which isneither clean nor renewable. While advancements in technology have madethe use of coal cleaner with less residual ash and lower atmosphericemission, coal cannot be used in all applications, particularly whereuse of liquid fuel is advantageous. Although coal can be processed intoa water-based slurry, such a slurry cannot be used where a low watercontent fuel is needed to avoid emission of certain oxides and/or otherpollutants, or where the water will cause damage to the equipment beingpowered by the combustion of the coal slurry.

Furthermore, coal slurry or fluid dispersions of coal still do notovercome the detrimental environmental effects caused by the combustionof coal for heat or energy generation. The type of coal typically usedtoday, called steam coal, or sub-bituminous coal, is not pure, andincludes a mixture of harmful heavy metals such as mercury and lead,toxins or other minerals such as sulfur that, when combusted, tend toadversely affect the combustion equipment and at the same time disperseinto the air and water resulting in potentially harmful effects onpeople and the environment.

In view of the problems of using coal and petroleum derivatives togenerate energy, various technologies have evolved to utilize renewablesources of energy from natural plant material through cultivation ornatural growth and regeneration of woody based, grass based orcultivated vegetable based plant materials, such as wood chips,agricultural by-products, cultivated crops or harvested naturallygrowing plants and the like. However, unless these materials are handledin a particular manner which includes their being dried and processedbundled, chipped, pelletized, cubed, or baled or heat treated, suchunprocessed natural plant products, commonly called “biomass,” aredifficult to use as fuel. The unprocessed biomass is typically eithertoo wet, too cumbersome or costly to handle and transport, too prone todecomposition or rot when in a stockpile, too bulky and difficult tofeed into conventional heat or energy generation equipment, or aresimply too full of non-combustible, non-natural fiber materials, orcontaminants such as metal, plastic, sand, gravel, dirt or other ashcausing products to effectively bring them from the field, farm orforest directly to a heat or power generating plant for use.

All solid fuels power plants, including coal and biomass power plantsare typically designed, engineered and built to use one type or class offuel and are not easily reconfigured to change from one fuel type toanother. For example, coal fired power plants cannot burn biomasswithout expensive and major engineering changes in their operationsystems, usually rendering them unable to revert to coal once thechanges to permit biomass combustion have been made. Biomass powerplants using certain types of woody based fiber including wood chips ina specifically designed boiler system cannot be fed into the systemalongside curbside garden variety aggregated biomass or crop generatedby-products without special handling and pre-processing of thealternative fuels. Furthermore these natural cellulosic materials arecomprised of a variety of differing cellular mechanical structures andchemical bonds which create their own sets of problems with respect toreduction of moisture content, management of size reduction oralteration, and particle production and handling to permit suitablecommercial feeding as a fuel into conventional biomass heat or energygenerating equipment.

The handling of biomass is problematic, and typically requires that adedicated biomass generation plant be specially engineered to usecertain specific types of biomass fuels. As discussed above, the biomassfuel type used in such a generation plant is typically notinterchangeable with another type of biomass fuel. Biomass can beaggregated, chipped or chopped, ground up, dried and burned, but not allbiomass can be mixed and processed homogenously, dried and burned withthe same equipment and in the same manner. In addition, raw, unprocessedbiomass type fuels (even if they have undergone a preliminary process,such as chipping or shredding) are not easily convertible or reducibleinto smaller more manageable and uniformly sized particles due to theirinherent diverse ligno-cellulosic chemical and mechanical cellularbonds.

Consumption of biomass for the production of heat is one of the oldestprocesses known to man, and the production of energy from heat to steamto electricity is also well established. However, as society focuses itsconcern on the environment and air and water quality, it has beenrecognized that the combustion of conventional biomass, even if plainlydried and burned, releases chemical components such as volatile organiccompounds (VOC's) and particulate matter generated during the combustionprocess that tends to foul the air and fill it with smoke, dust and ash.

Conventional biomass fiber fueled plants have become very costly andtime consuming to build because they must be engineered and designed toconsume biomass of a certain nature and to mitigate particulate andvolatile organic compound emissions resulting from the burning ofbiomass. Furthermore, these plants must operate on a 24 hour basisdaily, year in and year out in order to be cost effective producers ofgreen clean energy and clean heat. They cannot simply start and stop atwill, and are therefore used to produce electrical energy known as‘base-load’ or ‘firm base’ energy. They produce energy that costs thesame whether it is produced at 3:00 AM or at 2:00 PM. However, it iswell known that nighttime energy is less valuable than peak daytimeenergy.

Accordingly, the economics of biomass power plants are problematicbecause they do not fit all situations of affordable biomass consumptionor timely electrical demand. Furthermore, these types of plants arefixed in location and not mobile and because of the heavy nature oftheir construction are set into concrete and steel, hard wired andplumbed into power grid transformer stations, permitted in one area tooperate, permitted for one type of fuel and one type of ash output. Theyare also typically constructed proximate to a biomass fuel supply forwhich they are engineered, and which is generally located not more thanan eighty to one hundred mile radius from the plant. In somecircumstances, the biomass fuel supply is not even available year round,but is seasonally harvested, grown or aggregated.

One problem that has not yet been overcome simply by air drying orevaporative heating of the biomass until the biomass has a moisturecontent considered dry enough to combust, for example, under five (5)percent but generally less than 25%, is that all unprocessed and notspecifically heat-treated biomass is hydroscopic and hydrophilic. Drybiomass will not stay at the same moisture content if exposed tohumidity or weather. If it is dry, it will absorb moisture and becomewet once again. Whether or not the moisture is cellular moisture orsurface moisture, the water has a negative effect on the heat output ofcombusting biomass, as water is an extinguishing media that prevents ormaterially slows biomass combustion. Consequently, all unprocessed airdried or evaporative dried biomass that is non-specifically heat-treatedwill absorb ambient moisture.

Moreover, biomass dispersed into moisture laden fluids will absorb fluidand may prevent the biomass from being a suitable heat or energygenerating fuel. Even when the biomass is air or evaporative driedmechanically or otherwise, lignin and cellulose fiber bound together inthe dry biomass are hydrophilic and that allows the biomass to wick upand hold moisture thereby negatively impacting the combustion capabilityof the fuel product. In such cases, the biomass may require some form ofpre-heating or re-drying immediately prior to or along with combustion.

Furthermore, and most significantly, the mechanically and chemicallybound lignin and cellulose in biomass are not easily broken downsufficiently even through air drying and evaporative mechanical dryingto allow the biomass to be cost effectively and commercially reduced insize and consistent character, such as, for example, into a finelyground powder or even into minute micro or nano particulate sizesamenable to forming a slurry, suspension or liquid solution or acolloidal dispersion. Without changing the chemical and mechanicalnature of the biomass through specifically designed heat-treatingprocesses, the biomass within the slurry, suspension, liquid solution orcolloidal dispersion will remain hydrophilic and will retain theoriginal inherent chemical and vegetative compounds that contribute toVOC and particulate emission pollution when the biomass is combusted.

Recently, various technologies for heat-treating and processing biomasshave been developed which serve to alter the character of the biomass ina manner so as to provide a processed specially heat-treated biomassderived material for fuels that is hydrophobic and resists moisture wickup and absorption. These technologies remove VOC's and cellularparticulate matter from the biomass, such as, for example,hemicellulose, that produces smoke and harmful emissions on combustion,and impart a hydrophobic, friable condition to the remainingheat-treated biomass which can be more easily and cost effectivelyprocessed into smaller particles that are fine enough to form acolloidal dispersion when mixed with a fluid type carrier.

Use of these technologies reduces the weight of the biomass feedstockproduct, increases the entrained energy density per pound of theremaining product, and creates a homogenous dry solid that can bepressed into a pelletized or cubed product which can be transported overlong distances to plant locations where the processed solid biomassfuels can be stored, managed and consumed more cost effectively thanunprocessed pelletized or chipped biomass. These process treatments alsoresult in a product that is able to burn transparently with coal inun-modified coal fired power plants or in conventional biomass powerplants. The mix of biomass feedstock used to produce the end-processedproduct is not identifiable in the final heat treated product because itbecomes homogeneous, both in appearance and energy content.

One method involving specialty heat treating of biomass is known astorrefaction. There are several known methods of torrefactioncharacterized by the method and type of equipment and handling of thebiomass furnished product. Torrefaction is characterized by roasting araw biomass for a certain time and using a particular temperature curvein the absence of oxygen so as to prevent combustion of the biomass,remove hemicellulose and VOC's and moisture, to create a carbonized fuelproduct that has certain desirable characteristics which exceed thosefound in ordinary unprocessed biomass.

Supertorrefaction, or fast flash torrefaction, is a technology that, asits name implies, results in achieving an intermediate or end productmuch more rapidly than other methods. To effectively produce anacceptable end product, supertorrefaction requires the biomass feedstockto be pre-processed to reduce moisture in the feedstock and to ensurethat the feedstock particles are appropriately sized before furtherhigher temperature heat processing. The pre-processed biomass is thenheated with heat transfer fluid agents such as heat transfer oils,mineral oils or organic molten salts through a heat exchanger during thesupertorrefaction process.

Torrefaction involves a thermochemical treatment of previously air driedor moisture evaporated biomass at temperatures generally in the range of250 to 350° C. for a specified time. The time and temperature may bevaried depending on the type of biomass, its particle size, consistencyof mix of furnish, type of chemical and mechanical bonds of thecellulose and lignin present. The biomass, which is typically woodybased and generally having a pre-processing moisture content of lessthan 15-25%, is specifically heat-treated, roasted and charred in theabsence of oxygen until it breaks the lignocellulosic bonds, removes theVOC's and hemi-cellulose, burns off or gasifies some minerals, chemicalsand ultimately chars and embrittles the mix of lignin and carbon fiber.

Using the torrefication process, a desirable furnish product can becreated in a cost effective and appropriately commercial operatingmanner. Not all torrefaction technologies are suitable and not allautomatically result in a desirable output product. When the processingis properly done, water contained in the biomass, as well as superfluousvolatiles, primarily alcohols and hemicellulose, are released at lowertemperatures and the biopolymers in the biomass, such as, for example,higher temperature burning oils, cellulose, and lignin remain. Theprocess essentially fractures chemical and mechanical bonds, partlydecomposing the biomass, which gives off various types of volatiles, lowalcohols in gas form, some simple ash components and reducing orremoving or changing the character of certain minerals, salts from theresulting treated product.

The final torrefied biochar output product is a carbonized or charredsolid (not a charcoal), relatively dry (average 2-5% moisture content orless), and blackened into a torrefied biocarbon or bio-char materialthat retains carbon, carbonized lignin, some lower oils, some traces ofminerals, some gases, and some ash. The final product is hydrophobic andbrittle, rendering it easily friable and suitable for pulverizing into afine powder, and retains an energy content that is typically in therange of 9,500 BTUs per pound and 10,500 BTUs per pound. Under some timeand temperatures, the energy density can exceed 12,000 BTUs per pound.

Since the torrefied biocarbon or biochar product is hydrophobic, itrepels water and can be stored outdoors in most every outside climatecondition including moist air or rain without any appreciable wick upchange in moisture content or reduction of heating value, unlike the rawbiomass from which it is made.

Moreover, given the torrefied biocarbon or biochar may be easily andcost effectively reduced to a finely ground and pulverized powder inmicron, submicron and nano sized particles. Normally, this carbonizedproduct would be pelletized or cubed for handling, storage and foreventual transport. As a cubed or pelletized product it can becompressed and densified to a higher bulk and energy density than rawbiomass pellets or chips, and transported over greater distances at alower cost than conventional biomass fuels and it can be combusted inany conventional biomass power plant, or for heat or for energy in anyunmodified coal fired power plants. Leaving torrefied biochar in anunpelletized or uncubed state may allow undesirable dust to float in theair, which may create a nuisance storage condition. Excessive dust fromcarbonized product can create an unwanted accumulation of torrefied dustparticles which in a confined storage space may result in a combustibleor explosive dust-air mixture.

The char process may be altered to accommodate biomass types having amoisture content of, for example, 30-45% or greater. For example, whileheat-treatment torrefication of much drier biomass fiber is done atessentially low pressure or atmospheric pressure, a similar processresulting in similar if not an identical finished biochar end productmay be obtained using a process known as hydrothermal carbonization, orHTC.

The HTC process also heats the biomass but in the absence of oxygen andat a lower temperature and often with a longer exposure to heat, but atpressures of up to 700 psi or greater in an autoclave type environment.The resulting end product splits the raw biomass into a water ladenliquid phase and a cellulosic lignin and carbon laden phase. Thisprocess also separates certain salts and other minerals and chemicalsthat can be diverted in the liquid phase from the cellulosic carbonminerals in the solid phase, and removes the moisture from the solidphase in the same process.

The HTC process has its own particular benefits for productionoperations. Biomass products processed in this manner generally includeand begin with more wet (moisture laden) biomass fibers such as grassesand agricultural by-products, straws, wet agribusiness by-products andthe like. The end product of the solid phase is also a friable,hydrophobic cellulose and lignin product that has the same ultimategrinding ability, hydrophobicity, and workability as the above describedtorrefied product and can be used much as the torrefied productdescribed above, once liquid has been removed in one process or anothersuch as an evaporative process or a centrifugal process.

A newer type of conversion process, known as CELF, or Co-SolventEnhanced Lignocellulosic Fractionization, may also be used to processbiomass types that, for example, consist primarily of smaller particlesof woody based biomass, including such biomass as sawdust or shavings oragribusiness by-products such as hulls and seeds, shells, food or feed,processed waste such as cotton gin trash, grape pomace, crushed pits,feed mash or already ground smaller biomass fibers. This process isparticularly useful where the output of the components from the biomassfeedstock result in solutions which can be further processed and usedfor different purposes in different fuels, such as, for example,extracting alcohols and lighter oils, gasses, or solutions to beprocessed into gasoline or kerosene, or separation from heavier fuelssuch as biodiesel and ship's bunker fuels.

The CELF method processes the raw biomass furnish under lower heat andpressure than the previous processes resulting in a liquid component,which may include the solvents used to fractionate the components, waterand a dissolved lignin component which can then be separated, and asolid cellulose component, which may be particulate in form, that can beextracted and used individually or together as building blocks for otherfuels. Lignin and cellulose may then be processed into biofuel andcellulosic particles that will then be used or further processed tocreate submicron and nano particles by the same means of pulverizing andderiving powders as used with HTC or torrefication but, because of thechemical fractionization rate, it may be accomplished at a more rapidrate and at a lower temperature and shorter time to create a morediversely tailored output product.

A fourth process that may be used to create micron, submicron and minutenano-particles of biocarbon or biochar by specialized heat treatment isto use an abbreviated pyrolysis process where the biomass is processedin a much higher temperature environment, often at temperatures inexcess of 500 degrees Centigrade, albeit for a shorter period of time,than in the previous processes and whereby the inherent VOC's andhemicellulose are removed rapidly in the beginning of the process andthe resultant remaining cellulose and lignin product is carbonized orcharred but not completely pyrolized. In this form of heat treatmentprocess, however, the off-gassed water vapor is removed and certainpyrolysis type oils, lower heavy oil, and tar compounds which areusually the last to be consumed and are turned to a gas vapor which iscondensed or distilled in a conventional pyrolysis process, insteadremain in the residual lignin and cellulose biochar and are not removedfrom the cellular content of the carbon laden solid biocarbon.

The residual heavy oil and tar compounds that remain in the carbonizedbiochar particles after the abbreviated pyrolysis process increase theenergy content of the char particles. This type of abbreviated pyrolysisprocess may be considered an advantageous method because the residualbiochar itself has much of the energy that would otherwise have beenalready cooked out of it by the ordinary pyrolysis process and distilledinto another product or turned into ash. In any event, the remainingbiocarbon or biochar product, including the pyrolysis oil and tars, mustbe further processed to produce both a final torrefied biocarbon orbiochar having hydrophobic and friable qualities and higher energydensity.

All of the above processes provide a relatively dry (generally under 5%and more normally a 3% moisture content or less), particulate fuel thatcan be burned or gasified under the right conditions and in the rightequipment to provide green, non-polluting heat and energy with a carbonneutral footprint and a substantially reduced emission curve as comparedto conventional biomass or non-renewable fuels. However, the biocharproduct of the heat treatment processes described above is, withoutfurther processing and cautious handling, difficult to commercially bulktransport and store, dangerous to stockpile or deliver as a powderwithout causing a risk of airborne dust contamination or simplydangerous concentrations becoming an easily ignitable or even explosivemist, and difficult if not impossible to control and feed in a measuredand controlled way into a variety of commonly used heat and energygenerating equipment. It is also undesirable in a floating loose dustform with ordinary bulk non-processed biomass fuels used in dedicatedbiomass heat or energy generation equipment.

Moreover, one approach to controlling the dust and storage problems ofthe torrefied product in a cost effective manner has been to pelletizeor cube the torrefied biochar. However, pelletizing and cubing thebiochar limits its use to equipment and feed streams that are designedonly for such dry feedstock handling use.

Conventional liquid fuels today made from biomass are distilled,chemically cracked, fractionated, and refined through a number of highlycomplicated, expensive and critically engineered processes that destroyor remove the solid component from the fuel, extract sugars and/or othercompounds, and in the end create a bio-oil or bio-gasoline or alcoholbased fuel. No matter how these liquid biomass derived fuels are made,they are not solutions, liquid dispersions, or colloids because theyhave no particulate content in the final product. The process ofcreating a bio-gas, bio-oil, ethanol or methanol from raw biomassresults in a by-product waste, sludge, or agglomerated lignin andcellulosic sugar depleted fiber and ash product. These waste by-productsgenerally have been accorded little residual value, because theirsubsequent use relies on further processing the waste by-product tode-wet and dry the waste product before it can be burned or used as asoil amendment or component of animal feed without fostering undesirablebacteria or chemical compounds. Consequently, the conversion of thesewaste by-products has been complicated, problematic, and generally notcost effective.

What has been needed, and heretofore unavailable, is a practical,commercially viable and functional, low-cost process for producing andusing a natural biomass based carbon feedstock derived from many sourcesas a biocarbon or biochar based feedstock as a fuel to be used in avariety of commonly diverse heating and energy generation capacities,without requiring specifically dedicated, special purposed and designedand engineered biomass heating and electrical generating equipment. Sucha carbonized based feedstock should be able to be manufactured from avariety of different biomass furnishes, including various plant matter,including trees, bushes, agribusiness by-products, crops and grasses andother sources of raw biomass, for example, the waste product or sludgecreated by liquid biofuel manufacture, various types of shells, such as,for example, coconut, pistachio, walnut, almond, and the like. It shouldalso be able to be used from recycled scrap fiber or industrialcellulosic waste products including ground industrial waste wood,construction fiber, railroad ties, and paper and pulp waste. Such abiocarbon or biochar may be used in a number of diverse applications tocreate a fuel that can be used for the production of heat or energy. Insome cases the biocarbon may be incorporated into a non-aqueous fluidthat can be burned to produce heat or energy. The biocarbon may also beprocessed in such a manner that the liquid component of the raw biomassis separated and further processed to remove valuable minerals containedin the liquid component. Carbonized biomass based fuels should be ableto be mixed with existing petroleum based fuels or refined biomasssourced oil based liquid fuels resulting in overall lower cost, loweremission fuels while maintaining or improving the energy content of theresultant fuel. The biocarbon may also be processed by adding a suitableoil to the biocarbon produced by torrefaction and then polymerizing theoil to bind the biocarbon in a desired form or shape, such as an anode,granule, crumb, small cube or ball, briquette, mini-tubes, micro-tubes,pellets or other shapes. The present invention satisfies these, andother needs.

SUMMARY OF THE INVENTION

In its most general aspect, the invention includes a method forcompounding a non-aqueous biofuel derived from various solid butspecially processed biomass furnishes into a liquid fuel that may beused in engines such as diesel engines and other internal combustionengines, combustion turbines or aero-derivative turbines, conventionalboilers as well used in non-internal combustion devices where the fuelis burned to provide indirect generation of heat or energy, includingdiesel, gas or steam driven turbines.

In another general aspect, the specially processed biomass furnish is acarbonized biochar that may be manufactured using various processes. Inone aspect, the biocarbon is created using a torrefaction process thatprocesses raw biomass into a brittle, friable, hydrophobic, energydense, low moisture content material.

In another aspect, the biocarbon is created using a process that resultsin a brittle, friable low moisture content component and a separateliquid component. In one aspect, the separate liquid component may beprocessed to extract chemicals and minerals present in the liquidcomponent. The extracted chemicals and minerals may be further purifiedor processed.

In still another aspect, the feedstock for the special process used tocreate the biocarbon may include not only raw biomass, but also thewaste product from processes that create liquid biofuels such asbio-gasoline, bio-oil, or various other energy containing liquid fuels,such as, for example, ethanol and methanol.

In another aspect, the biofuel is a colloidal dispersion of micronizedand nano-particulated biocarbon in a petroleum or oil-biofuel base. Sucha dispersion is advantageous in that it provides for supplementation ofa petroleum based fuel in such a manner as to maintain or increase theenergy content of the fuel while reducing the amount of petroleumproduct consumed while reducing the harmful environmental impact of useof the petroleum based fuel.

In still another aspect, the biofuel is added to heavy fuel oil such as,for example, bunker fuel oil to dilute or blend with the fuel oil,reducing both the percentage of harmful sulfur or other mineralcomponents of the bunker fuel and reducing the overall price of theblended or diluted fuel while maintaining or increasing the energycontent, lubricity, cetane value and other characteristics of the heavyfuel oil without increasing the amount of harmful emissions resultingfrom the combustion of the blended mix of biofuel and bunker fuel oil.

In another aspect, the invention includes a method of making a greenbiofuel based on renewable biomass feedstock, comprising: receivingbiomass feedstock; processing the biomass feedstock to produce a lowmoisture biocarbon; particulating the low moisture biocarbon; andforming a colloidal fluid from the particulated low moisture biocarbonand a non-aqueous combustible liquid.

In another aspect, processing the biomass furnish to produce a lowmoisture biocarbon includes torrefaction of the biomass feedstock. In analternative aspect, forming a colloidal fluid includes dispersing theparticulated low moisture biocarbon in the non-aqueous combustibleliquid. In one alternative aspect, the non-aqueous combustible liquid isbio-oil. In another alternative aspect, the non-aqueous combustibleliquid is a petroleum based liquid. In still another alternative aspect,the petroleum based liquid is diesel fuel. In yet another alternativeaspect, the petroleum based liquid is oil. In still another alternativeaspect, the petroleum based liquid is #6 Residual Fuel Oil or Bunker Cfuel oil.

In still another aspect, particulating the low moisture biocarbonproduces a low moisture biocarbon having a particle distribution in therange of 10 micron to 100 nanometers. In one alternative aspect, theparticle distribution has an average particle size of 200 nanometers to400 nanometers.

In yet another aspect, the low moisture biocarbon is hydrophobic. Instill another aspect, the low moisture biocarbon is friable.

In another aspect, the biomass feedstock includes waste from a processthat produces a combustible liquid from raw biomass. In still anotheraspect, processing the biomass feedstock produces a low moisturebiocarbon and a liquid component.

In a further aspect, the invention includes a method further comprisingextracting a selected material from the liquid component. In onealternative aspect, the selected material is selected from the groupconsisting of chemicals, salts and minerals. In another alternativeaspect, the selected material is lithium.

In still another aspect, the invention includes a method of producing agreen biofuel based on renewable biomass feedstock, comprising:receiving a renewable biomass feedstock; processing the renewablebiomass feedstock to produce a friable hydrophobic biocarbon;particulating the friable hydrophobic biocarbon into submicron sizeparticles; and forming a colloidal fluid by combining the submicron sizeparticles with a combustible liquid. In an alternative aspect, thecombustible liquid is a bio-oil. In another alternative aspect, thecombustible liquid is a petroleum based liquid. In still anotheralternative aspect, the combustible liquid is a blend of bio-oil and apetroleum based liquid. In still another alternative aspect, thecombustible liquid is a petroleum based liquid blended with bunker oil.In another alternative aspect, the combustible liquid is #6 ResidualFuel Oil or Bunker C fuel oil.

In yet another aspect, the invention includes a method of producing abiofuel from a biomass feedstock, comprising: receiving a biomassfeedstock; processing the biomass feedstock to produce a low moisturebiocarbon; particulating the low moisture biocarbon; and combining theparticulated low moisture biocarbon with a combustible liquid. In onealternative aspect, combining the particulated low moisture biocarbonwith a combustible liquid forms a colloidal dispersion of theparticulated low moisture biocarbon in the combustible liquid. In stillanother alternative aspect, the combustible liquid is #6 Residual FuelOil, Carbon Black Oil or Bunker C fuel oil.

In yet another aspect, processing the biomass feedstock includes heatingthe biomass feedstock to form a solid energy dense friable biocarbonwith no VOC's and no remaining hemicellulose to pollute or smoke whencombusted and a liquid and a condensable gas from which bio-oil can bedistilled. In still another alternative aspect, the liquid is processedto extract a selected chemical from the liquid for fuel orpolymerization. In another alternative aspect, the liquid is processedto extract a selected mineral or chemical compound from the liquid. Inyet another alternative aspect, the liquid is processed to extract aselected salt from the liquid.

In another aspect, the invention includes a green liquid fuel;comprising a particulated solid biomass derived fuel dispersed into anon-aqueous liquid to form a combustible colloidal suspension. In analternative aspect, the solid biomass derived fuel has an averageparticle size of less than or equal to 10 microns. In anotheralternative aspect, the solid biomass derived fuel has an averageparticle size in the range of one micron to 100 nanometers. In anotheralternative aspect, the non-aqueous liquid is petroleum based. In yetanother alternative aspect, the petroleum based non-aqueous liquid isfuel oil. In still another alternative aspect, the non-aqueous liquid isa liquid biofuel. In another alternative aspect the micronized solidbiomass derived fuel is misted and blended with powdered pulverized coalto be used in a co-fired combustion process.

In another general aspect, the invention includes a system and method tocontinuously carbonize/torrefy biomass into a bio fuel. In onealternative aspect, the continuous carbonization/torrefaction processutilizes a reactor to carbonize/torrefy a blend of uncarbonized biomassmixed with a non-aqueous bio fuel, the bio fuel acting as a heattransfer fluid, The heat transfer fluid surrounds the biomass,lubricating the biomass blend as it is pumped through the continuousreactor, and also improving and supplementing the process of heattransfer from the walls of the reactor to the biomass. In anotheraspect, the reactor is heated by a recycling flow of molten salt. Inanother aspect, the reactor may be a tube within a tube reactor whereinmolten salt is recycled around the interior tube to heat the blend ofbiomass and heat transfer fluid flowing past at least a portion of thereactor. In another aspect, the invention includes pumping the blend ofuncarbonized biomass and carbonized bio fuel heat transfer fluid througha pipe, with at least a portion of the pipe immersed in a tank, bath orvat containing a recirculating molten salt system.

In still another aspect, the output of the continuouscarbonization/torrefaction reactor may be piped into a pyrolysis reactorfor producing pyrolysis oil, pyro-gas and other by-products. In onealternative aspect, the pyrolysis reactor may be a ‘tube-in-tube’reactor heated to a temperature sufficient to induce pyrolysis of thecarbonized/torrefied biomass blend flowing at a controlled rate, timeand temperature through the pyrolysis reactor. In another alternativeaspect, the heat supplied to the pyrolysis reactor may be provided by arecirculating molten salt system.

In another general aspect, the invention includes a system and processfor carbonizing/torrefying a blend of uncarbonized biomass and bio fuelin a batch method. In this aspect, uncarbonized biomass of varying size,dimension or biomass type and composition is loaded in massive lose bulkform into a tank or container where the uncarbonized feedstock remainsin place, the tank is closed and an airless environment is created, biofuel is added by pumping into the container, while the tank remainsclosed. The tank is then heated from the outside by a heat exchangerusing a recirculating molten salts fluid and at the same time in theinside biomass mix by recirculation of the biofuel heated and pumpedinto the tank until the biomass loaded into the tank or container iscarbonized/torrefied. In an alternate aspect, the bio fuel may act as aheat transfer fluid and be recycled through the reactor tank and heatedto provide the heat energy for the carbonization/torrefaction process orpyrolysis. In another aspect, the tank or container may be submerged ina vat or tank of molten salt to provide heat for thecarbonization/torrefaction process.

In still another aspect, the invention includes a system for carbonizinga biomass, comprising: a pump adapted to receive a blended feedstock ofnon-carbonized biomass and bio fuel, the bio fuel both providing a heattransfer medium for the biomass and a means of lubricating the bio massso that it will flow within and through the reactor by being pumped andpushed by the subsequent additional biomass and biofuel blend beingprocessed; and a reactor configured to continuously receive the blendedfeedstock and to carbonize the uncarbonized biomass of the blendedfeedstock, the bio fuel of the blended feedstock also providing for amanaged and regulated and controlled enhanced transfer of heat to theuncarbonized biomass. In an alternative aspect, heat is provided to thereactor using a recycling molten salt stream, the molten salt having afirst temperature level in excess of 350 C and raising upwards to 500 Cor greater as desired.

In yet another aspect, the reactor outputs a continuous stream of asecond blend containing carbonized biomass and bio fuel; and furthercomprising a pyrolysis reactor configured to continuously receive thesecond blend and transform the carbonized biomass into a pyrolyzedproduct. In an alternative aspect, heat is provide to the pyrolysisreactor using a second recycling molten salt stream, the molten streamhaving a second temperature range exceeding 350 C and raising upwards toin excess of 500 C or greater as desired.

In yet another aspect, the invention includes a system for carbonizingbiomass, comprising: a sealable container configured to receive a blendof uncarbonized biomass and an already processed colloidal biofuel, thebiofuel providing enhanced heat transfer to the biomass being carbonizedwithin the sealed container; a lid for sealing the container; a means ofremoving air from the container if it is not displaced by the biomass,and a heat source for heating the sealed container. In an alternativeaspect the container has an appropriate means of measuring andregulating the flow of product within the container, the temperature ofthe product and removing the excess steam and VOC gas and cookedhemicellulose which are being off-gassed in the process. In anotheraspect the container is able to extract and to recycle the off-gas in aseparate burner outside the container to continuously heat thecontainer's extracted fluids and to keep the pressure inside thecontainer as close to ambient as possible. In an alternative aspect, theheat source is a recycling flow of molten salt flowing through a heatexchanger or pipe system within the container or outside the container.In another alternative aspect, the heat source is a recycling flow ofthe bio fuel.

In another aspect, a suitable liquid or oil, such as pyro oil, may beadded to the biocarbon produced by the torrefier. The resultant mix maythen be further processed, such as by heating the mix in such a way asto polymerize the liquid or oil so that the polymerized liquid or oilbinds the biocarbon. In some alternative aspects, the mix is formed intoa desired shape, such as granules, crumbs, small cubes or balls,mini-tubes, micro-tubes, pellets, anodes, briquettes or mini-briquettesor other smaller or larger shapes.

Other features and advantages of the present invention will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings, which illustrate, by way of example, theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical representation illustrating one embodiment of aprocess used to manufacture a torrefied biocarbon or biochar from rawbiomass.

FIG. 2 is a graphical representation illustrating another embodiment ofa process used to manufacture torrefied biocarbon or biochar from rawbiomass.

FIG. 3 is a graphical representation illustrating another embodiment ofa process used to manufacture torrefied or pyrolyzed biocarbon, biocharand pyro oil from raw biomass.

FIG. 4 is a graphical representation illustrating one embodiment of aprocess for manufacturing a liquid biofuel using the torrefied biocarbonor biochar manufactured using the embodiments of FIGS. 1-3.

FIG. 5 is a graphical representation illustrating one embodiment of asystem for carbonizing/torrefying a blend of uncarbonized biomass andbiofuel such as a dispersion of torrefied biomass and petroleum orpyrolysis oil.

FIG. 6A is a graphical representation illustrating an embodiment of acontinuous carbonization/torrefaction reactor in accordance with FIG. 5.

FIG. 6B is a cross sectional view of reactor of FIG. 6A.

FIG. 6C is graphical representation of an embodiment of a continuousprocess utilizing the reactor of FIGS. 6A and B together with apyrolysis reactor and associated accessories.

FIG. 7 is a graphical representation of an embodiment of the presentinvention illustrating a carbonization/torrefaction reactor andassociated sub-systems for processing uncarbonized biomass in a batchmode.

FIG. 8 is a graphical representation of an embodiment of the inventionof FIG. 7 that is heated using a recycling molten salt heat transferfluid to provide heat energy to the carbonization/torrefaction reactor.

FIG. 9 is a graphical representation of an embodiment of the inventionillustrating details of a continuous carbonization/torrefaction reactor.

FIG. 10 is a graphical representation of an embodiment of the inventionillustrating details of a continuous pyrolysis reactor that may be usedin conjunction with the continuous carbonization/torrefaction reactor ofFIG. 9.

FIG. 11 is a graphical representation of an embodiment of the inventionillustrating various process that can be carried out on processedbiomass output from the reactors of FIGS. 9 and 10.

FIG. 12 is a graphical representation of an embodiment of the inventionillustrating a continuous process for producing carbonized/torrefiedbiomass by pumping a blend of biomass and heat transfer fluid through apipe or channel immersed in a tank, vat, or container filled with moltensalt.

FIG. 13 is a graphical representation of an embodiment of the inventionillustrating reactor that can be used to produce carbonized/torrefiedbiomass in a batch mode.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Various embodiments of a process for manufacturing a petroleum orbio-oil based renewable biofuel will now be described. In one generalembodiment, the feedstock moves through the reactors and other processesin a continuous process. In one particularly advantage variation of thisembodiment, the feedstock comprises raw recyclable matter that iscarried by a heat transfer fluid (HTF).

In such a general embodiment, the feedstock being processed is movedthrough the process by pumping the feedstock within a pipe or channeladapted to transport and process the moving feedstock in an airless,oxygen free environment. It is contemplated that the feedstock is ablend of biomass and one or more separate heat transfer fluids. The heattransfer fluids act as a lubricant and heating component, and typicallyhave a viscosity sufficient to move the biomass and heat transfer fluidthrough the process.

In this general continuous embodiment, the pipe or channel is directedthrough a heat tank or surrounded by coils through which another heattransfer fluid, such as, for example, molten salt, is recirculated. Thetime and temperature and duration of the movement of the mix ofuncarbonized feedstock and carbonized heat transfer fluid in the pipeand heat of the molten salts bath are controlled to suit the process.Excess steam and pressure build up during the process may be removedfrom the pipe or channel using vacuum pumps. In some embodiments,off-gas extracted from the process stream may be used as fuel toperpetuate the heating function to heat the biomass-carbonized heattransfer fluid mix, the molten salt, or anywhere else in the processstream where use of the heat generated using the off-gas may be desired.A heat exchanger circulating the fluid may be remote or integrated andthe flow and temperature of heat transfer fluids and molten salts may bemanaged according to results desired.

In this general embodiment, the use of moving parts (excepting pumps) iscompletely minimized so the flow can be regulated and increased to movelarge volumes of cellulosic biomass continuously through the process. Atthe end of the carbonization/torrefaction process, the carbonizedproduct is extracted from the end of the pipe or channel and may then beeither used as, or directed through further processes, such as apyrolysis process to create a liquid or gaseous pyrolysis oil, biochar,and/or gas.

The essence of this embodiment is a continuous means to torrefy andgasify cellulosic biomass in large volumes and control the quality,volume and output through the use of one heat transfer fluid blendedwith unprocessed biomass, and the use of another heat transfer fluid,such as molten salt, to provide heat to the above described feedstockblend.

One advantage of this general embodiment is that the use of thecarbonized heat transfer fluid as a transport media provides not only anefficient heat and transport media which can be used without the need toextract a material, such as, for example, an aqueous transport media tomove the unprocessed biomass through the carbonization process, but itimproves the conveyance of heat energy into the biomass from the moltensalt heat energy transfer fluid into the biomass. This allows the rateof continuous carbonization of the biomass to be more preciselycontrolled, and improves the overall efficiency of the process byavoiding the need to extract the carbonized biomass from the transportmedia.

In a second general embodiment, biomass is converted into carbonizedbiomass in a batch mode by heating the biomass within a closed tank orother container until a desired level of carbonization is reached. Incontrast to the first general embodiment described above, the biomassdoes not move, and is processed in place.

In this second general embodiment, large chips or pieces of bark andtree limbs or even logs are placed into a containment tank or vessel.The volume of the containment tank or vessel may have a volume that isas large as a sea container or rail gondola car. Even larger containmenttanks or vessels may be used, such as, for example, a ship's hold, or aportion of a ship's hold.

The containment tank or vessel is filled with biomass which can be ofvarying size and dimension and even have difficult to remove unwantedpieces of metal, rock, stone that could not otherwise be practicallyremoved or ground up beforehand and a lid is attached to seal the tankor vessel. The containment tank or vessel will typically have multipleopenings formed in a wall, lid, or bottom of the tank or vessel to allowfor the introduction of a heat transfer fluid such as a viscouscarbonized heat transfer fluid that may initially be at ambienttemperature, or it may be heated to an elevated but non-combustibletemperature. One such heat transfer fluid that may be used is GRC88™green renewable fluid distributed by Permanente Corporation.

In one alternative embodiment, the biomass to be carbonized is immersedin the heat transfer fluid. The heat transfer fluid is heated and pumpedthrough the biomass in the tank and then extracted from the tank andrecirculated so that the heated fluid encapsulates and surrounds andmoves through the biomass and torrefies or carbonizes it over a periodof time. The lid and the tank or vessel may have valves and pipes toenable the metering and measuring of the inflow and recirculation of theheat transfer fluid through the tank or vessel.

In one alternative embodiment, air may be removed from the sealed tankor vessel using, for example, a vacuum pump. Pumps may also be usedprovide for the extraction of off-gas and steam vapor from the tank orvessel as the carbonization process proceeds. As described above, theoff-gas may be used for reheating the heat transfer fluid either throughdirect heat exchange or by burning the off-gas to provide for indirectheating of the heat transfer fluid.

In yet another alternative of the second general embodiment, when thedesired torrefaction or carbonization process has begun, additionalheating of the tank or vessel may be provided raise the temperature ofthe tank or vessel and its contents. Such additional heating may beprovided by, for example, heat exchange between piping or channels onone or more sides, lid, or bottom of the tank or vessel. These pipes orchannels allow for a heat exchange fluid, such as, for example, moltensalt, to be pumped around the exterior of the tank or vessel, heatingthe tank or vessel. This heat is then conducted into the interior of thetank or vessel through the walls, lid, and/or bottom of the tank orvessel to further add heat energy to the contents of the tank or vessel.

In some embodiments, the piping or channels described above may beconfigured similarly to a radiator. The sides of the radiator aretypically heavily insulated with an insulator, such as, for example,rock wool, such that the heat produced through the molten salts flowingthrough the pipes radiates through the walls of and into the containmenttank or vessel. The temperature of the molten salt may be controlled andmonitored while circulating through the radiator and kept within a rangeof operating temperature. In some embodiments, different molten saltshaving different temperature ranges and freeze points can be used inseparate heat transfer tubes or heat exchangers to provide a morediversely managed range of heat treatment of the biomass beingcarbonized.

When a desired temperature is reached within the tank or vessel, or whenthe process is completed in either the continuous or batch embodimentsdescribed above, the circulation of the molten salt heat transport fluidis stopped. The molten salt may then be removed from piping or channelsthrough which it has been circulated, and pumped into an insulatedcontainment vessel for later use. It is a known fact that well containedand insulated molten salts will hold heat sufficiently that they willlose only a degree or two over a month's time. Such reuse is advantagein that it provides for decreased cost of processing the uncarbonizedbiomass.

It will be appreciated that the molten salt may be stored in differentinsulated containers, allowing molten salt of different temperature tobe used. For example molten salt having a temperature suitable fortorrefaction may be used in the torrefaction process to carbonize thebiomass, while molten salt having a temperature suitable for pyrolysismay be used to pyrolyze the torrefied biomass. In on embodiment, a pipeas in the first general embodiment is exposed to a radiator in which iscirculated molten salt having a temperature suitable for torrefaction ata first portion of the pipe to continuously torrefy the biomass blendbeing pumped through the pipe. After the blended biomass has been pumpedthrough a sufficient length of the pipe to torrefy the biomass, theblend containing the now torrefied biomass may encounter a secondportion of the pipe being heated by a second radiator through which amolten salt having a temperature suitable for pyrolysis is beingcirculated.

Similarly, such a dual radiator system may used to head the tank orvessel of the second general embodiment. Additionally, it should beunderstood that in such an embodiment, two separate radiators may not benecessary, provided appropriate valves and piping are provided to allowthe input of a single radiator to be supplied with two or more moltensalt sources, each of the sources providing molten salt at a desiredtemperature.

FIG. 1 illustrates one embodiment of a process 10 for treating rawbiomass to manufacture a low moisture torrefied biocarbon or biochar. Inthis embodiment, biomass of various types 12, 15, 20 , 25, 30 and 32 areaccepted for processing to materially and substantially alter the formof the biomass from a high moisture laden or moisture compatible,hydrophilic, bulky and difficult to handle solid into an extremely lowmoisture content, hydrophobic, non-moisture compatible, friable solid ofa more dense energy content than the original biomass furnish and into aproduct that may be further processed.

The feed stock for the process may be almost any plant or plant derivedmaterial, such as, for example, trees, tree parts, logs, or log trim 12,grasses 15, agricultural by-products 20, wood chips, 25, waste from theproduction of ethanol 30, and scrap wood 32. Examples of by-product fromwood use operations include, but are not limited to, sawmill residue,chips, sawdust and shavings, hog fuel including bark, and logging slash.Examples of agricultural waste include, for example, but not limited to,nut shells or husks, pits, ground wood fiber, pomace, hulls, straw,cotton gin trash, vine or tree pruning or even woody based fiber andbark, limbs, trunks and branches from removed orchard trees, nursery oryard tree branches and trunks, remaining after one or more trees havebeen cut down, semi-processed and residual agribusiness by-products, andthe like. Such furnish biomass is bulky, difficult to stockpile,expensive to transport, full of moisture or foreign matter includingrefuse, dirt, sand, metal, plastics, ash contaminants and otherunacceptable particulate matter, and costly to process and typically hasa very low heating value per unit of as-is weight. The aggregation ofthe feedstock may include chipping, grinding, crushing, andoccasionally, washing and cleaning to remove field debris, and thenwindrow piling the feedstock. The biomass may also be compacted by itsown weight in vans and open topped trailers used to transport thebiomass to a secondary use or disposal site, or the biomass may be piledin windrows. At this stage of the aggregation, however, the biomass isnot pelletized or cubed, is generally laden with moisture, and subjectto energy loss through decomposition if the biomass is not properly airdried when being stockpiled.

In another embodiment, the waste sludge, lignin and cellulose contentremaining from the production of ethanol, bio-oils, or distillation ofbiomass may also be used as a feedstock. This waste product may be usedas a solitary feedstock, or it may be combined with the raw feedstocksdescribed above.

The various types of biomass 12, 15, 20, 25, 30, and 32 typicallyundergo a process 35 to reduce the size of the biomass to a desiredparticle size for efficient processing. Process 35 may involve, forexample, running the raw biomass through a hammer mill, a ball mill, agrinder, or some other mechanical process that cuts, shreds or otherwisereduces the size of the individual pieces of biomass to a desired size.The processed biomass may also be screened and/or washed to removeforeign matter.

In the embodiment of FIG. 1, the processed feedstock is stored inappropriate storage bins, stockpiles, containers or silos 40. In someembodiments, each type of raw biomass is stored separately from anothertype, although in some instances this separate storage is not necessary.As shown in FIG. 1, the various types of biomass may also be blendedusing a blender 45 to provide a raw biomass feedstock having desiredcharacteristics and/or properties.

Depending on the type of raw biomass available, the raw biomass may beprocessed through a dryer, such as a rotary drier 50, although othertypes of driers may be used. Once the raw biomass is dried to a desiredmoisture level, the dried biomass may be transferred to a holding hopper55, or may be transferred to a feed hopper 60.

Alternatively, when the moisture content of the raw biomass is suitablefor further processing, or if the process can accommodate a highmoisture level, the raw biomass may be directly transferred to feedhopper 60. At this point in the process, the raw biomass is processedinto a char, various embodiments of which will be discussed in moredetail below.

In the embodiment shown in FIG. 1, the raw biomass held in hopper 60 isfed through an airlock 62 into reactor 65. In this embodiment, theairlock 62 is used to prevent air from entering reactor 65 and thereactor is used to torrefy the raw biomass in the absence of oxygen tocreate a hydrophobic and friable biochar. During torrefaction, thebiomass is substantially changed in its appearance, chemistry,workability, and suitability as a fuel, resulting in a speciallyheat-treated intermediate biocarbon or biochar product that iscompletely homogeneous in appearance regardless of the feedstock orfeedstocks used to create the biochar, and if, or when, blended withother biochar products similarly processed results in an end productthat is similar in content and performance characteristics from anyother biomass feedstock variety in the mix of original biomass furnishused.

Torrefaction is a pyrolytic thermochemical treatment of biomass attemperatures that typically range from 280 to 350° C. and for varyingperiods of time in the absence of oxygen. The thermochemical treatmentis generally carried out in reactor 65 under atmospheric, or slightlyabove atmospheric pressure in the absence of oxygen. During thetorrefaction process, the water contained in the biomass is vaporizedand released from the biomass, and the biopolymers (cellulose,hemicellulose and lignin, among others) present in the biomass partlydecompose or deconstruct, and bonds are broken apart, giving off varioustypes of volatiles and consuming hemicellulose in the process. When theprocess is complete, the remaining solid, dry, blackened material iscommonly referred to as a “torrefied biocarbon” or “torrefied biochar.”

The torrefied biochar resulting from the original biomass typicallyloses 20% to 25% of its mass and usually not more than 10% of itspre-processed weight to caloric heating value, densifying the energycontent in the remaining resultant product and increasing the overallcaloric value with reduced weight measure with no appreciable increasein volume. The volatiles given off during the torrefaction process maybe collected and used as a heating fuel for the process. Typically,hemicellulose is consumed early in the process which beneficiallyremoves the future combustion source of smoke, much particulate matterand lesser energy containing materials.

After the biomass is torrefied it can be compressed, crushed,pulverized, powdered and densified. In many cases, the char is formedinto briquettes or processed into pellets using conventionaldensification equipment. Torrefied biochar is relatively hydrophobic,and will not wick up but instead repels water and thus can be storedoutside where it may be exposed to moist air or rain without appreciablechange in moisture content or heating value, unlike the original biomassfrom which it is made. Moreover, torrefied biomass biochar will not rot,compost, decompose or otherwise degrade in stockpile over time.

After the torrefaction process is completed, the torrefied biochar isremoved from reactor 65 through airlock 70, and transferred to a biocharcontainment area 75, bin or vessel for storage of the biochar beforefurther processing. Waste heat from the torrefaction process may beextracted from the reactor 65 and conveyed to dryer 50, when a dryer isused to decrease the moisture content of the raw biomass. This processis advantageous in that not only does it reduce the costs associatedwith drying the raw biomass, but it also renders the process more“green” in that less fuel needs to be consumed simply to dry thebiomass. The off-gas heat and the VOC's that result from torrefactionmay provide a fuel and heat combination that may be burned at highertemperatures for use in the rotary drier 50. Use of the off-gas heat andVOC's in this manner tend to render the heat source substantially lesspolluting.

In some embodiments, the biochar may be densified by pelletizing orcubing the biochar after it is extracted from the reactor and cooled. Atthis stage, the biochar is extremely friable and its dust tends to floatin the air, which may make the torrefied biocarbon or biochar dangerousto store in loose bulky, dusty, powdered form.

In another embodiment, gas resulting from the torrefaction process maybe pulled off or vented from the reactor and sent to gas separator 72.The flammable fractions separated out may be extracted, condensed into aliquid or solid form, and be either stored for future use, or sent toanother process for use either as a solvent, transportation medium, orenergy source. In another alternative embodiment, the separated gas maybe used to power various equipment in a plant, such as, for example, agenerator or genset 80.

FIG. 4 illustrates an embodiment wherein the biochar, instead ofdensification, pelletization or cubing, is ground or otherwisepulverized and processed to produce a fine dispersible low moisturecontent powdery material. The pulverization process may be controlled toproduce the fine material in a variety of particle sizes and particlesize distributions. The fine dispersible material may be combinedthrough a comminution process with a non-aqueous solvent or fluid toprovide a liquid biofuel.

The liquid biofuel may take several forms. For example, the particulatedbiomass char may be simply mixed into a slurry using a non-water basedsolvent. Depending on the viscosity of the fluid and the size of theground biocarbon or char particles, and the effects of gravity however,the slurry may separate with time, which is disadvantageous. The liquidbiofuel and biochar may be kept in a solution by continuallyrecirculating the fluid and particle blend through a static mixerdevice.

In one embodiment, the liquid biofuel is created by forming a colloidaldispersion of the pulverized torrefied biomass or biochar and thesolvent. In this process, the particle size of the biochar is made smallenough so that once the particulated biochar is dispersed into thesolvent with or without a surfactant, a colloidal dispersion is formed.One of the principle characteristics of such a colloidal dispersion isthat the dispersed particles do not settle out of solution and remainuniformly blended therein throughout the lifetime of the colloidalsolution.

It has been determined that biochar particles having a particle size inthe range of 1.0 micron to about 100-150 nanometers with a mode of 200to 300 nanometers can be sufficiently dispersed into a non-aqueousviscous medium such as bio-oil fuel or fuel oil or a mix of the two soas to form a colloidal dispersion. It will be understood, however, thatdifferent ranges are possible depending on the desired properties, suchas blending medium, viscosity of the blending fluid and heat content,among other characteristics, of the final dispersion. For example, theparticulated biochar may have differing particle size distributions,such as ten weight percent being particles of 10 microns or less, withother reduced fractions being distributed so that the overall particlesize distribution allows forming a colloidal dispersion. The process mayalso use surfactants to prevent a charged biocarbon particle fromattracting to and agglomerating to other particles within the fluidblend over time.

It will be understood that the amount of biochar dispersed into thenon-aqueous solvent will affect the viscosity and heat content by volumeof the resultant colloidal dispersion. Thus, the liquid biofuel may beformulated, designed, and manufactured having characteristics that aremost desirable for use in particular applications.

As shown in FIG. 4, various types of biochar may be stored in storagebins 405, 410 and 415. In the embodiment shown, each type of biochar isprocessed by pumping or otherwise conveying 420, 425 or 430 the biocharto a mill or grinder 435. Alternatively, a single mill or grinder couldbe used to process more than one type of biochar without departing fromintended scope of the invention.

As the biochar is milled or ground into a fine pulverized material, itmay be further screened, processor or classified to remove ash, silica,salts, or other undesirable foreign or minerals as it is transferred toconditioning vessels where the biochar may be treated or processed asnecessary, such as, for example, by catalytically treating the biocharwith heat and pressure, to provide the energy content/density, moisturecontent and the like characteristics desired for the resulting biofuel.Optionally, the conditioned pulverized biochar may be stored in theconditioning vessels, hoppers or bins 440, 445, 450. Since thepulverized biochar has a very fine particle size, it may be advantageousto combine the pulverized biochar with a liquid carrier, such as asolvent or light fuel oil and a surfactant. Mixing the pulverizedbiochar with the liquid carrier is advantageous in that it mitigates thedust related problems associated with the storage of finely pulverizedcombustible biochar and prevents agglomeration of single fine particles.This mixing step may be done immediately after the biochar is ground, orit may take place later in the process stream, depending on the designof the solid and fluid content and the safety requirements of themanufacturer.

Referring again to FIG. 4, in embodiments where different types,particle sizes or consistency (or in the case where one or more biochartypes have been fluidized by mixing with a liquid carrier), the variousbiochar feed streams may be combined in a mixer 455. Mixer 455 mayachieve mixing of the various feed streams using a mechanical mixer, oralternatively, mixing may be accomplished using a static mixer 457 bypumping the various feed streams through the static mixer.

The output of mixer 455 may be stored in container 460, before beingused a feed for dispersion/comminution/blending process 465.Alternatively, the output of mixer 455 may be fed directly intodispersion/comminution/blending process 465.

During the dispersion/comminution/blending process 465, the biochar fromthe mixer 455 or container 460 is combined with a selected liquid orblend of liquids and if desired surfactants to form a dispersion whereinthe particles of biochar are dispersed throughout the liquid in a mannersuch that the biochar does not fall out of solution or settle due togravity when the solution is stored. As described above, theparticulated biochar from mixer 455 or container 460 is combined with asolvent or fluid 470, and/or bio oil 475, which may be a pyrolysis oil,and/or a viscous fuel oil 480, such as, for example, heavy fuel oil(also called bunker C). Pumps 485 pump the desired fluid or mix into thedispersion process machinery 465 where the fluid is mixed with thepulverized biochar.

Once a liquid dispersion of biochar and selected solvent is createdhaving a set of desired properties, such as, for example, a desiredviscosity and/or energy density, the dispersion is pumped using pump 490either to storage containers 495, or for further disposition, includingdistribution, to a tank truck 500.

Depending on the type of raw biomass that is available, other processesmay also be used to create the solid cellulosic and lignin carbonbiochar which is then dispersed into a liquid fuel. As will bediscussed, not only may it be advantageous to employ these processesdepending on the available raw biomass, but the output of the processmay include both liquid and solid phases, each of which may beadvantageously used to provide energy used in the process itself, orwhich may be further processed to provide a biofuel.

In an alternative embodiment shown in FIG. 4, pump 490 may pump thedispersion through a static mixer 492 to ensure that the dispersion iscompletely formed before it either stored or pumped into a tank truck.In some embodiments, the tank truck may also have a recirculating systemto pump the dispersion from the tank and into a static mixer to ensurethat the dispersion stays mixed during storage in the tank truck orwhile being transported.

In yet another embodiment, dispersion may be tapped from either the tanktruck or from storage tanks 495, pumped using a pump 510 to a mixer orblender 515, and then blended with ground/blended biochar, resulting ina blend that can be used as a heat transfer fluid 520 formixing/blending with uncarbonized biomass, such as is described above.

In another embodiment, illustrated in FIG. 2, a process 200 is shownwhere raw biomass 205, which may be screened, ground or chipped, is fedthrough an airlock 210 into a reactor 215 where the raw biomass 205 isheated in the absence of oxygen and at a lower temperature thantorrefaction and pyrolysis and often with a longer exposure to heat, butat increased pressures of up to 700 psi in an autoclave typeenvironment. Heat is provided by a heat source 220, which may be fed bya portion of the off-gassing heat from the process and/or biomassconsumed for heat, and the reactor may be pressurized using expandedgases put off by the biomass being consumed inside the reactor process.Additionally, the heat may be supplemented with added pressure of heatedgasses retained and re-introduced using a pump 225.

The end product of this process splits the raw biomass into a watervapor laden liquid phase 235 and a bio-carbon laden “sludge” phase 240.The liquid phases and carbon laden phases are extracted from the reactorthough suitable means, such as a vacuum pump or an airlock 230.

The liquid phase 235 may contain certain chemicals, salts and otherminerals that can be extracted or separated from lignin within theliquid phase using techniques known in the art. These chemicals, saltsand other minerals may be further processed and sold, thus providing asecondary income stream from the heat treatment process, while theresultant biocarbon appears as a biochar solid phase and may be used asa biofuel.

The biocarbon laden phase 240 may be further processed using a dewettingdevice 245. The output of the dewetting device is a liquid 255 and asolid appearing biochar. The solid biochar is transferred to a biocharcontainment 250 vessel or container as has been discussed previously.Depending on the properties of the liquid 255, that liquid may befurther processed to remove water and used as a component of a biofuel,or it may be used to provide energy, such as for example, as asupplement to heat source 220, to the process to increase the efficiencyof the process.

In another embodiment, the process of FIG. 2 may be modified usingco-solvent enhanced lignocellulosic fractionization to process biomasstypes that consist primarily of smaller particles of woody basedbiomass, including such biomass as sawdust or shavings or agribusinessby-products such as hulls and seeds, shells, food or feed, processedwaste such as cotton gin trash, pomace, ground pits, feed mash oralready ground smaller fibers. This process is particularly useful wherethe output of the components from the biomass furnish can be used fordifferent purposes in different fuels, such as, for example, extractingalcohols and lighter oils and gasses to be processed into gasoline orkerosene, or with heavier fuels such as biodiesel and ship's bunkerfuels or in the extraction of essential oils in the processing ofbiochemical elements extracted from the cellular structure of thebiomass.

In this embodiment, the raw biomass feedstock, which may be cleaned andscreened, with impurities removed, is sized reduced as much aspractical, is placed in a vessel with certain chemicals, such as, forexample, if the end desire is for a light fuel solvent, tetrahydrofuran(THF) and is treated using lower heat and pressure, and for a similar orshorter time, than in the other embodiments described herein, resultingin a liquid component consisting of THF, certain fluids and solvents;water; a dissolved lignin component; and a solid cellulose componentthat can be used individually or together as building blocks for otherfuels. Lignin and cellulose may then be processed separately intobiofuels. The solid cellulose particles that result from the process andare filtered or otherwise separated from the liquid component aresuitable to be used and combined with other biocarbon feedstock tocreate micron, submicron, and nano-sized particles powders by thepulverizing and deriving processes described previously.

In another embodiment, illustrated in FIG. 3, a process 300 of creatingtorrefied biomass or biochar is shown that includes creating micron,submicron and minute nano-particles of biochar by using an oxygen freeabbreviated pyrolysis process where the biomass is processed in a muchhigher temperature environment, often at temperatures in excess of 500degrees centigrade, albeit for a shorter period of time than needed forfull pyrolysis and previously described processes. In this embodiment,inherent VOC's and hemicellulose are removed rapidly in the beginning ofthe process and the resultant remaining product is carbonized or charredbut not completely pyrolized or made into a charcoal. In this form ofheat treatment process, however, the pyrolysis oils, lower heavy oil,and tar compounds which are usually the last to be consumed and areturned to a gas vapor and distilled in a conventional pyrolysis process,instead remain in the residual biochar are not removed from the cellularcontent of the carbon laden biochar.

Raw biomass 310 may be used as a feedstock for the pyrolysis reaction orit may also be used to fuel the pyrolysis reactor 315. As shown, rawbiomass, which may be pre-screened and/or washed to remove contaminantssuch as stone, gravel, sand, salt, metal, plastic or other ash causingsubstances, and then ground, chipped or pulverized, is fed from supplysource 305 into pyrolysis reactor 315. Depending on the process used,air locks 320, 325 may be used to prevent oxygen from entering thereactor when feedstock is added to the reactor for processing, and whenbiochar is removed from the reactor, respectively. The char output maybe further processed at block 330 before being transferred to a biocharcontainment vessel or container 335. Gases given off during thepyrolysis process may be extracted at box 340, and, in some embodiments,used to fuel or supplement the fuel burned in burner 345 that providesheat to the pyrolysis reactor.

As also shown in FIG. 3, an alternative embodiment provides for theaddition of already processed biocarbon, unprocessed biomass, andpyrolysis oil to the biomass fuel 310. In another embodiment, the gasextracted at box 340 may be directed through a separation unit 350. Theoutput of the separation unit can either be stored bio-oil or pyrolysisoil in storage tank 355, or it may be used to heat the carbonized heattransfer fluid within heat loop 362 by being burned in heater 360. Apump 370 is used to recycle heated heat transfer fluid through aradiator in thermal communication with the pyrolysis reactor 315 back tothe heater.

The heavy oil and tar compounds remaining in the biochar particles afterthe abbreviated pyrolysis process shown in FIG. 3 increase the energycontent of the char particles. This type of abbreviated pyrolysisprocess is advantageous because the residual biochar itself has much ofthe energy that would otherwise have been ultimately cooked out of it bythe ordinary pyrolysis process.

Since the specially heat treated biochar from any of the embodimentsdescribed above is suitable to be finely ground and pulverized into apowder in micron, submicron and nano sized particles, and since thoseparticles could then be combined with a suitable non-aqueous liquid,such as, for example, a petroleum based liquid, a new fuel comprised ofheat treated biomass solids carried in a liquid form is created. As aliquid, the biofuel is easier to handle, transport, store, distribute,and consume than densified versions of the biochar, such as pellets orcubes.

The biochar created by the various embodiments described above is alsocompatible with petroleum or liquid biomass fuels, in the form of afluid or as a solid suspended in a liquid, and stored as a liquid,pumped and conveyed as a liquid and delivered up to any variety ofconventional liquid fueled heat or energy generating machinery andequipment in a consistent, measured and reliable manner. The biochar,dispersed into a non-water based fluid or as a pseudo liquid which wouldact, burn, combust and deliver energy similarly to current liquid fuels,becomes a new liquid fuel alternative. It will contain an increasedcaloric value over the non-water based fluid alone, but will also havesubstantially less environmental impact resulting from, for example,reduced sulfur, mineral, heavy metal and ash contents. The added solidcarbon sourced component of liquid biofuel is green, renewable andcarbon neutral, thereby reducing the carbon footprint of the energybeing produced.

The biooil and pyro oil feedstocks and biocarbon feedstock, before beingdispersed into a blended liquid biofuel produced in accordance with thevarious embodiments of the invention, generally have less inherentcaloric value, as measured in BTUs per pound or per gallon, than thesame unit of volume of petroleum based liquid fuel. Until now, there hasbeen no reasonably practical method, beyond de minimis increases due toimproved refining techniques, to increase the inherent caloric energyvalue of either bio fuel based liquids or petroleum based liquids. Thenovel liquid fuel resulting from the various embodiments of theinvention where specially processed biocarbon or biochar solids aresufficiently micronized and dispersed or blended into a non-water basedbiofluid fuel base or petroleum hydrocarbon based fuel results in acombined higher inherent energy value per unit volume or weight and atthe same time provides environmentally desired features to the blendedproduct.

The liquid biofuel based on the biochar of the various embodiments ofthe invention is easier and safer for all purposes than a powdered,pelletized or cubed form of processed biomass to transport and store,deliver and convey, and may be used in directly in burners, misters,boilers, or gasifiers, compression ignition and combustion engines, andturbines that are designed to burn conventional petroleum distillates orliquid green energy oil derived fuels or solid coal boilers. The energyprovided by such a fuel produces increased energy, gallon for gallon, orpound for pound, with a reduced carbon footprint, reduced atmosphericemissions and reduced residual left-over ash when compared to othersolid raw biomass fuels and all other solid non-biomass fuels.

It is contemplated that the biofuel manufactured in accordance with thevarious embodiments of the invention may be used as a standalone fuel tobe used in burners and engines such as diesel engines, or it may also beused to fuel a jet or combustion turbine engine. The biofuel can beblended with a bio-oil liquid for a 100% green liquid solution or apetroleum based fuel oil for an environmentally improved petroleum basedfuel oil. It is also contemplated that the liquid biofuel may be used asan additive to petroleum based fuels, such as heavy fuel oil or bunkeroil marine diesel fuel or to make renewable green carbon black oil, orgreen renewable activated carbon feedstock.

One example of such a use would be to incorporate the liquid biofuel ofthe various embodiments described above into low sulfur bunker fuel oil.Such low sulfur fuel currently sells for between $800 and $990 per ton.Liquid biofuel product in accordance with the embodiments of theinvention would have insignificant amounts of minerals such as sulfurand would not remove or counteract or react adversely with any of thedesired qualities of low sulfur bunker fuel oil or conventional bunker Cheavy fuel oil including those related to lubricity, cetane rating, andthe combustion components of low sulfur or conventional bunker fuel oil.

Liquid biofuel may be priced lower than petroleum based bunker fuel. Itmay be added to low sulfur bunker fuel oil such that it comprises, forexample, 25% to 40% of the total volume of the fuel mix, therebysignificantly reducing the cost of the combined fuel per gallon or perton, while not compromising the efficacy of the primary bunker fuel oilcomponent and without increasing any adverse effects of sulfur or otherminerals, yet maintaining, or increasing, the energy value of thecombination fuel. Even if this blended mix resulted in increased theconsumption of the fuel oil mix to provide the same operating parametersfor ship's engines, the increased amount of energy provided at a lowercost in the blend more than offsets the marginally increasedconsumption.

On a cost basis, the blended fuel can be mixed with conventional bunkerfuel and can achieve a lowered overall sulfur percentage to enable morecost effective compliance with laws requiring reduced sulfur emissionsof fuels consumed within 200 miles of a coastline. It is anticipatedthat savings of $150 to $200 per ton of fuel is possible by admixing thecolloidal liquid biofuel into low sulfur bunker fuel oil, with savingsof similar magnitude expected when mixed into conventional higher sulfurcontaining bunker C fuel.

The biochar colloid dispersion in accordance with the variousembodiments of the invention may also be used to fortify the productknown as Biodiesel. Biodiesel is generally regarded as having lessenergy density or less heating value than petroleum based diesel fuels.Dispersing a colloidal suspension of biochar in biodiesel cansubstantially increase the energy density of the biodiesel. For example,adding and dispersing approximately three pounds of biochar with a lowerheating value net energy density of 10,000 BTU/pound or greater to aB100 biodiesel having a net lower heating value of 119,550 BTU/poundresults in a fuel with a combined caloric value of 149,500 BTU/pound.This new colloid dispersion creates a fuel exceeding the net heatingvalue of #2 diesel, which is between 130,000 and 142,000 BTU/pound.

Similarly, a biochar colloidal dispersion in accordance with the variousembodiments of the present invention may also be used as an additive toheavy fuel oil or Bunker C fuel. Should the addition of the biocharresult in increased viscosity of the Bunker C, that viscosity can befurther controlled using conventional means, such as heating the BunkerC to improve flow, or through the use of Dimethyl Ether (DME) to reduceviscosity. Combining a biochar dispersion with Bunker C and using DME toreduce and control viscosity allows the formulator to enhance the BunkerC by dispersing larger amounts of biochar in the colloid, whilemaintaining a workable viscosity. Thus, the combination provides a fuelwith increased heat or energy density/content at a lower price and witha workable viscosity than could otherwise be achieved through use ofBunker C alone.

Such a fuel would be capable of being used in a two cycle low speedSulzer type diesel engine found in most ships currently. Alternatively,it could be misted and burned in an aero-derivative combustion turbinewith or without pre-gasification. Such a fuel could also be mistedand/or mixed and blended with other fuels and burned in conventionalboiler applications or in direct fired or co-fired misted coal or dieseloil applications.

Other advantages of the liquid biofuel manufactured in accordance withthe various embodiments of the present invention are that the combinedfuel would not increase the known safety risks associated with liquidpetroleum based fuels nor would it contribute to the risk of explosionof the combined fuels, either during use, storage or transportation.Furthermore, any spillage of the biofuel not yet combined with anypetroleum based fuel will not result in any environmental contaminationof air, soil or water. Moreover, because the particularized biomassbiochar is dispersed in a non-aqueous solvent, such as a bio-oil, fueloil or other suitable solvent, it eliminates storage, delivery, fuelmoisture and blending problems that would otherwise result from usingblended oil and water-based dispersions, such as water-based coalslurries.

Moreover, such a fuel is “green” in the sense that it is produced fromgrown plant matter and also considered renewable and sustainable becauseit is derived from biomass that is continuously produced. Furthermore,the production and use of biofuels in accordance with the variousembodiments of the invention are environmentally protective because theraw biomass furnish, if not used in this manner, would decompose orotherwise simply be discarded, dumped into landfills or disposed of inother dry waste depositories. Further, since the raw biomass is notdumped into landfills, or otherwise left to simply decompose, theproduction of the novel biofuel of the embodiments of the inventionreduces the proliferation of harmful environmental gasses such asmethane, which is known to be twenty times more harmful to theatmosphere than carbon dioxide.

In another embodiment, the biochar colloidal dispersion of the presentinvention may be incorporated into the torrefaction and/or pyrolysisprocedures. For example, a biochar colloidal dispersion produced using aprocedure such as that shown in FIGS. 2-4 may be mixed with groundbiomass to enable the biomass to be more easily pumped through pipes andthen into a torrefaction reactor.

In yet another embodiment, the biochar colloidal dispersion may beheated using a heater and then mixed with the biomass. In this way, theheated biochar colloidal dispersion imparts heat to the biomass so thata heated biomass/dispersion mixture, which may be a slurry or sludge isprovided to the reactor. In this embodiment the heated biochar colloidaldispersion may be characterized as a heat transfer fluid.

In one embodiment, the heater or heat exchanger that is used to heat thebiochar colloidal dispersion heat transfer fluid is a structure to allowthe use of molten salt as the heat source. The molten salt may bemaintained at a temperature in the range of 700 to 1400 degreesFahrenheit in a closed cycle pumping circuit, which may include astorage tank, preferably insulated. The molten salt is pumped using anappropriate pump from the storage tank, to the heat exchanger forheating the biochar colloidal heat transfer fluid, and back to thestorage tank. In some embodiments the storage tank may be omitted butthe molten salts needs to be kept above its freeze temperature.

While the use of molten salt is described in terms of heating thebiochar colloidal dispersion, it will be understood that molten salt maybe used as the heat source in any of the embodiments described herein.

The heated biochar colloidal dispersion may have a wide range totemperature, for example, from ambient temperature 700 degreesFahrenheit.

FIG. 5 illustrates one process for using torrefied biocarbon or biocharcolloidal dispersion as a transfer fluid to transport unprocessedbiomass through the torrefaction process. As illustrated, biomass fromhopper 600 is transported to a mixer 620 where is it mixed with biocharcolloidal dispersion. In one embodiment, the biochar colloidaldispersion is mixed with the biomass at room temperature, and thenpumped by pump 635 into torrefaction reactor 625. Torrefied biocharcolloidal dispersion and the torrefied biomass are output from thereactor at output 630. At this point, the torrefied biomass may beseparated from the biomass/biochar colloidal dispersion slurry or sludgeand reused in a closed cycle system. Those of ordinary skill in the artwill understand that under certain conditions the amount of biocharcolloidal dispersion in the recycling closed system may need to bereplaced or topped up to keep the system in optimal operation condition.It will also be understood, while not shown in FIG. 5, molten salt maybe used as the heating medium of the reactor 625.

In this embodiment, the biochar colloidal dispersion assists in heatexchange between the heated reactor and the biomass. This occurs becausethe biochar colloidal dispersion itself is a good heat exchange media,filling in the spaces that exists between the chips and chunks of thebiomass particles. Processes gases, steam, and other unwanted gases maybe removed from the slurry using known techniques. The process operateswithout substantially elevated pressure.

In yet another embodiment, illustrated in part in FIGS. 6A and 6B, thetorrefaction reactor may comprise a length of “pipe within a pipe” ofadequate length to allow the biomass/biochar colloidal dispersion slurryor sludge to reach torrefaction temperatures and “cook” the slurry in acontinuous manner. Once cooked, the torrefied biomass and biocharcolloidal dispersion may be separated with the biochar colloidaldispersion being reused and the torrefied biomass being either used asis, or undergoing further processing as described above to be convertedinto biochar colloidal dispersion.

As illustrated in FIG. 6A, the pipe 710 through which thebiomass/biochar colloidal dispersion is pumped may be surrounded by alarger pipe 715 FIG. 6B. This larger pipe 715 may be of sufficientdiameter to allow large amounts of molten salt to be pumped through asubstantial length of the piping at a large enough velocity so as tomaintain a temperature sufficient to keep the salt in a molten state.Appropriate fittings are used attach the pipe 715 to supply pipe 745 andoutput pipe 750. In the embodiment illustrated, molten salt receivedfrom pipe 715 into pipe 750 flows into an input of pump 730. The moltensalt is then pumped through a heater 740 to raise the temperature of themolten salt, which will be reduced during its travel through pipe 715 byexchanging heat from the molten salt into the biomass/biochar colloidaldispersion slurry or sludge. While the heater 740 is illustrated asbeing located between the output of pump 730 and pipe 745, the heatercould be located along pipe 750 so that the molten salt is heated beforeit is input into the pump 730. In yet another embodiment, there may bemultiple pumps and heaters disposed in the molten salt closed system toensure that the temperature and flow of the molten salt stream ismaintained. The molten salt system may also include one or more valves735 as needed to control the flow of molten salt through the system, orto allow one or more sections of the system to be drained, repaired, orreplaced or to store unused volumes of molten salt above its freezingpoint. .

FIG. 6B is a cross section of pipe in a pipe reactor construction shownin FIG. 6C. The orientation of inner pipe 715 which contains thebiomass/biochar colloidal dispersion within pipe 720 which contains themolten salt is clearly shown. Surrounding pipes 715 and 720 may be ahousing 720. Housing 720 will typically be insulated to assist inreducing temperature loss of the molten salt due to contact with ambientair.

In one embodiment, biomass and biochar colloidal dispersion are combinedand pumped into the reactor pipeline of FIG. 6A at room temperature. Invarious embodiments, the viscosity of the biochar colloidal dispersionmay be adjusted to provide a viscous thick “crème” form that facilitatesthe transport of the biomass through the reactor system. Pumps havingthe capability of pumping extremely viscous “chunk” fluids are wellknown in the art, such as, for example, pumps used to pump concretethrough large diameter hoses and pipes.

Once the biomass/biochar colloidal dispersion slurry enters the reactorof FIG. 6A, heat is exchanged from the molten salt into the slurry,where it is gradually heated until the slurry begins to torrefy. Factorssuch pipe diameters, pipe length, expected heat exchange rates, and flowrate through the pipe carrying the biomass/biochar colloidal dispersion,as well as the temperature of the molten salt, must be considered whenengineering the pipe reactor so that the torrefaction process operatesin a continuous way while accepting un-torrefied biomass/biocharcolloidal dispersion in the input end and outputting torrefied biomassat the output end of the reactor. Such engineering factors are wellknown in the art.

After the torrefied biomass/biochar colloidal dispersion slurry passesout of the pipe reactor, the slurry may be pumped through a cooler/heatexchanger so that the slurry cools to a lower temperature so that theslurry does not combust when it comes into the presence of oxygen. Theslurry output may be a viscous mixture of biochar colloidal dispersionand torrefied chunks of biomass (cellulose) in the form of chips or bitsof fiber. The slurry may then be pumped through a blender or grinder toreduce the size of the torrefied biomass particles. The viscosity of theresultant slurry may then be adjusted as need by adding pyro-oil orbio-oil to the slurry.

As described above, the slurry of torrefied biomass and biocharcolloidal dispersion may either be separated into dual streams, or maybe further processed as a unified stream. For example, the torrefiedbiomass/biochar colloidal dispersion stream may be pumped into ananother reactor pipe designed to provide the conditions necessary toconvert the torrefied biomass/biochar colloidal dispersion intopyrolysis oil (“pyro-oil”). At the higher temperature reached by such apyrolysis pipe generator, the biomass is pyrolyzed and the biocharcolloidal dispersion in the slurry is gasified and can be condensed intopyrolysis oil.

Another advantage of the system described above is that the entireprocess is performed in the absence of oxygen in the system. This allowsthe torrefaction process to be performed without the biomass flashinginto a fire. Furthermore, the entire process is performed with a minimumof moving parts where the flow of carbonized product is managed by pumpsand where such product flow will not be jammed or impinged by movingparts in a reactor such as augers, drag conveyors, wheels or rotatingcylinders.

Another embodiment of a continuous processor is illustrated in FIG. 6C.In this embodiment, biomass blended with heat transfer fluid 802 ispumped into a tube 815 within a tube 810 carbonizer 830. Heat is addedto the outer tube 810 of the carbonizer 830 by circulating a heattransfer medium such as molten salt through the outer tube 810 tocarbonize/torrefy the biomass/heat transfer fluid being pumped throughthe inner tube 815. Off gas from the carbonization/torrefaction processis extracted or vented through exhaust pipes 825, and can be recycledand burned for providing heat to the process.

After the biomass blend has been pumped through a sufficient length ofthe carbonizer 830, the unprocessed biomass is converted into carbonizedbiomass which then can flow into pyrolizer 835, whose output iscondensed gas 837, non-condensible gas and ash 839 that can each beseparated from the pyrolyzed stream. The pyrolyzed output may then beseparated and cooled and the condensed gas stored as pyrolysis oil 840,the non-condensible gas used to refuel the heat required by the processitself and the ash removed to provide a useful end product such as asoil amendment.

FIG. 7 is a graphic depiction of an embodiment 900 in which thefeedstock for the carbonization process is static and does not move,enabling a batch mode of carbonization in accordance with variousprincipals of the present invention.

In this embodiment, cellulose 902_of non-uniform size is loaded into acontainer or tank 904. The container or tank is then sealed by applyinga lid 906 to the container or tank. Heated heat transfer fluid 908, suchas, for example, GRC88, is pumped (910) into the sealed container toimmerse the non-uniform cellulose in the tank. The heat transfer fluidis then recycled through the interior of the tank and further heated tobring the temperature of the blend within the tank to a temperaturesufficient to induce carbonization/torrefaction of the non-uniformcellulose biomass in the tank. Air present in the tank or container canbe extracted, along with off gas produced by the carbonization processby a vacuum pump 912. The off gas may be further processed into variousoils, fluids and solids or used to perpetuate the heat transfer processitself.

FIG. 8 is a graphic depiction similar to the illustration in FIG. 7, butuses a recycling molten salt system to provide heat for thecarbonization/torrefaction process. In this embodiment, the sealed tankor container 950 containing the uncarbonized cellulose is in thermalcommunication with a recycling molten salt bath or radiator 955. Thesalt bath or radiator is insulated 952 to direct the heat energycontained in the molten salt into the reactor tank or vessel. The heater957 for the molten salt may be fueled using off gas extracted from thereactor tank or container, pyrolysis oil, or other fuel 959, 960. Thecirculation process is accomplished with few to no moving parts as thefluids are pumped and the contents of the reactor tank or vessel remainstatic.

FIG. 9 is a graphic diagram of one embodiment 1000 of a continuousprocess for torrefying biomass as described above. Biomass 1002 and heattransfer fluid 1008 such as, for example, GRC88, are combined by pumping1004 them into a static mixer 1006. The heat transfer fluid lubricatesflow of the biomass through the process. This heat transfer fluid may beat a temperature that, even if elevated above ambient temperature, isnot so high as to induce combustion of the raw biomass.

In order to provide heat (or additional heat) to the reactor 1010, apump 1012 recycles a heat transfer fluid, such as, for example, acirculating flow of molten salt, through either the space between wallsof a tube in tube type reactor 1010, or through the walls of the of thereactor by way of a radiator or heat exchanger in thermal communicationwith the walls or the reactor. From the onset the flow of both biomassand heat transfer fluid should fill the void such that no accumulationsof air occur and a vacuum 1014 on the gasses is constantly being drawnto prevent pressure build up in the reactor. Various openings in thereactor may be used to extract steam and off gases 1016, 1018 from theinterior of the reactor. In a continuous process such as illustrated,various fractions of off gasses may be extracted using different ventsalong the length of the reactor. If the off gases contain moisture, theymay be directed to a condenser 1020 to remove the moisture. As describedabove, the off gas may be used for various purposes, such as by burningoutside the reactor itself to provide heat 1022 for either the heattransfer fluid within the blend of biomass being torrefied or to heatthe molten salts.

FIG. 10 is a graphic diagram illustrating a pyrolizer in accordance withthe principles of the present invention. After being processed by theprocess reactor illustrated in FIG. 9, the output stream of thatreactor, which now includes a carbonized biomass and heat transfer fluidblend 1052, is flowed through a pyrolysis reactor 1050. As before, offgas may be extracted 1054 and either used for heating or condensed 1056to provide pyrolysis oil that may be stored 1058 or used for heating orcombined with carbonized biomass. Molten salt 1062 at a temperaturesufficient to heat the reactor and carbonized biomass blend to a levelsufficient to pyrolyze the blend may be used to heat the pyrolysisreactor. The output 1057 of the pyrolizer is segregated and cooled andstored 1060 for future use either as a fuel or as a heat transfer fluid.

FIG. 11 is a block diagram illustrating one embodiment 1100 of a processfor further processing the cooled biocarbon from either thecarbonization or pyrolization process described above. The cooledbiocarbon 1105 is ground, filtered 1110, washed and de-wetted 1115, andthen processed to separate out ash 1120 and other unwanted impurities1125. The filtered biocarbon 1127 may be further dried 1130, and thentransported, preferably by pumping, to a static mixer or mixers 1135,wherein bio-oil, pyrolysis oil, or petroleum fuel oil, or all of them,are mixed with the dried biocarbon and then further ground or processedthrough appropriate particle creation machines. The output of the mixeror mixer-blenders provides a bio fuel that is very low moisture, hashigh energy value, and is adapted to various uses. For example, it maybe further blended with pyrolysis oil 1160 and stored, formed into adispersion such as GRC88 fuel 1170 and stored 1175, formed into a heattransfer fluid 1185, or other blends or mixtures 1180 that are usable asa green sustainable heat or combustion source.

FIG. 12 is a graphic diagram illustrating one embodiment 1200 of acontinuous torrefaction/carbonization process wherein the blend 1215 ofuncarbonized biomass 1205 and heat transfer fluid 1210 does not flowthrough a tube in a tube type reactor, but is pumped 1220 through a pipeor enclosed channel 1225 that is configured to have a portion thatpasses into or through a molten salt tank or bath 1235. In thisembodiment, biomass 1025 and heat transfer fluid 1210 are blendedtogether 1215 and then pumped through a pipe using a heavy duty pump1220 such as, for example, a modified concrete pump. As with otherembodiments described above, the contents of the molten salt bath arerecycled using an appropriate pump 1240, and the temperature of therecycled molten salt is maintained or adjusted with a heater, which mayuse off gas, natural gas, or other fuels for generating the heatnecessary to heat the molten salt stream.

As described above, heat from the molten salts is conveyed through thewall of the pipe or enclosed channel into the biomass product flowingwithin the pipe or channel until it is torrefied and carbonized to theextent desired. The product being processed may be processed in a directflow through the reactor, or may be recirculated through the reactor inone or more passes until the desired level of carbonization is achieved.The product may be mixed in the pipe during processing, such as, forexample, a static mixer 1245. The product may then be pumped into acooling zone 1250 where it is taken to a reduced temperature such theproduct will not ignite or combust when exposed to air. Various pumps1227, 1230 and other means may be used to extract and/or vent off gasesfrom the biomass blend as it is processed. The gas output of the processmay be further processed to generate pyrolysis oil, or it may be cooled.

FIG. 13 is a graphical depiction of another embodiment 1300 of acarbonizer/torrefier in accordance with various principles of thepresent invention. A reactor vessel 1305 is stuffed with uncarbonizedbiomass. The uncarbonized biomass may be placed in the reactor alone, orit may be combined with heat transfer fluid, such as, for example, GRC88green fuel. The reactor is sealed, and lowered into a vat or tank 1310filled with a second heat transfer fuel 1315, such as, for example,molten salt at a temperature sufficient to induce torrefaction. In thisillustrative example, the molten salt is maintained at a temperature ofapproximately 650 degrees centigrade. Various pumps 1317, vents 1323,valves 1319, 1321 are used to control the process and extract off gas asneeded.

In another embodiment, a suitable liquid, such as pyro oil, may be addedto the biocarbon (torrefied biomass) after torrefaction. The additionalliquid may be added prior to or after the biocarbon is particulated.After the liquid is added, further processing may be carried outpolymerize the liquid so as to bind the biocarbon particles together andif desired compress them into a more dense matrix. As will be apparent,the biocarbon may be formed into a desired shape, such as, for example,an anode, granules, crumbs, small or large cubes or balls, mini-tubes,micro-tubes, pellets, briquettes or mini-briquettes, or the like andsuch shape will be maintained by the polymerized liquid binder while theshaped biocarbon is stored, shipped, or used.

One advantage of the various embodiments of the present invention,especially when the static tank or vessel process is used, is that theprocess may be used to carbonize or pyrolyze used rail road ties andsleepers, used boat and pier dock planks, old telephone poles and crossarms, old bridge timbers, old cooling tower wood components, and oldtreated decking. The disposal of these types of ‘treated wood’ is verydifficult because they are often treated with creosote and coal tar,copper chromium arsenate, bromates, bromides, Wolman salts, and otherpreservatives. Additionally, they may have imbedded metal, spikes,nails, bolts, cable and other metallic material that is typicallyremoved or separated from the wood before processing. Such removal andseparation is difficult, expensive and problematic. Furthermore, theadvantages allow the safe processing of wood that is salvaged fromstructures destroyed or damaged during hurricanes or flooding often hasbeen submerged in sewage or contaminated water, or has been painted withlead based paint.

The various embodiments of the present invention are capable ofaccepting these types of woody biowaste as feedstock for carbonizationand or pyrolization. Where the feedstock is ground up or is in smallchunks, it can be used as feedstock for the continuous processingembodiments, and if it provided in large chunks, piles or poles, it canbe processed using the static embodiments of the present invention.Advantageously, these feedstocks are carbonized and/or pyrolyzed at suchhigh temperatures that the process removes the biological toxins andchanges the chemistry or chemical treatment components sufficiently toenable disposal or repurposing as fuel, burial as a soil amendment,disposal in a dump.

While particular embodiments of the present invention have beendescribed, it is understood that various different modifications withinthe scope and spirit of the invention are possible. The invention islimited only by the scope of the appended claims.

I claim:
 1. A method of making a green biofuel based on renewablebiomass feedstock, comprising: receiving biomass feedstock; combiningthe biomass feedstock with a biocarbon colloidal dispersion into ablend; and pumping the blend through a length of first pipe having afirst diameter surrounded by second pipe having a second diameter largerthan the first diameter, the second pipe being supplied with acontinuous flow of heat exchange fluid, the length of the first pipehaving an input end for receiving the blend, and an output end foroutputting a second blend of torrefied biomass and biocarbon colloidaldispersion generated within the length of the first pipe.
 2. The methodof claim 1, wherein the heat exchange fluid is molten salt.
 3. Themethod of claim 1, further comprising particulating the second blend tohave a particle distribution in the range of 10 micron to 100nanometers.
 4. The method of claim 3, wherein the particle distributionhas an average particle size of 200 nanometers to 400 nanometers.
 5. Themethod of claim 1, wherein the torrefied biomass is friable.
 6. Themethod of claim 1, wherein the biomass feedstock includes waste from aprocess that produces a combustible liquid from raw biomass.
 7. Themethod of claim 1, wherein generating the second blend produces a lowmoisture biocarbon, a condensable gas and a liquid component.
 8. Asystem for carbonizing a biomass, comprising: a pump adapted to receivea blended feedstock of noncarbonized biomass and bio fuel, the bio fuellubricating the bio mass; a reactor configured to continuously receivethe blended feedstock and to carbonize the uncarbonized biomass of theblended feedstock, the bio fuel of the blended feedstock also providingfor enhanced transfer of heat to the uncarbonized biomass.
 9. The systemof claim 8, wherein heat is provided to the reactor using a recyclingmolten salt stream, the molten salt having a first temperature.
 10. Thesystem of claim 8, wherein the reactor outputs a continuous stream of asecond blend containing carbonized biomass and bio fuel; and furthercomprising a pyrolysis reactor configured to continuously receive thesecond blend and transform the carbonized biomass into a pyrolyzedproduct.
 11. The system of claim 10, wherein heat is provide to thepyrolysis reactor using a second recycling molten salt stream, themolten stream having a second temperature.
 12. The system of claim 10,wherein the pyrolyzed product is a pyro oil.
 13. The system of claim 12,wherein the pyro oil is added to carbonized biomass and then polymerizedto maintain the carbonized biomass in a desired form or shape.
 14. Thesystem of claim 8, wherein the blended feedstock includes feedstockderived from a plant shell.
 15. A system for carbonizing biomass,comprising: a sealable container configured to receive a blend ofuncarbonized biomass and a biofuel, the bio fuel providing enhanced heattransfer to the bio fuel; a lid for sealing the container; a heat sourcefor heating the sealed container.
 16. The system of claim 15, whereinthe heat source is a recycling flow of molten salt.
 17. The system ofclaim 15, wherein the heat source is a recycling flow of the bio fuel.18. The system of claim 7, wherein the condensable gas or liquidcomponent may be further processed to form a pyro oil.
 19. The system ofclaim 18, wherein the pyro oil is added to the low moisture biocarbon,and the mixture of low moisture biocarbon and pyro oil is furtherprocessed to polymerized the mixture in a desired form or shape.
 20. Thesystem of claim 19, wherein the desired form or shape includes agranule, crumb, small or large cube or ball, a tube or mini-tube,micro-tube, pellet, a briquette, a mini-briquette, or other large orsmall shape.